Hi, my old (1990) Hegner Multimax-18 speed control has stopped working (max speed all the time regardless of the knob setting). Being an EE I probed the speed control PCB and I believe it's functioning OK. However the tachometer pickup coil on the motor (see photo) reads open when I measure it. If it's really a coil and not some Hall Effect sensor or something I would expect a few hundred or maybe a few thousand ohms when measuring the coil but it's definitely reading open. So it appears to have failed, which would explain why the speed control isn't working.
Can anybody tell me:
1. Is the pickup on the motor just a simple coil? Or something more exotic? This saw was built in 1990 so I suspect it's not too exotic.
2. Can I buy a replacement coil? If so, where? A replacement motor is something like $750 so definitely not going that route
3. Does anyone have fried motor they'd like to sell, so I can salvage its coil?
The coil is shown in the third photo, it's the device above the motor shaft with two wires coming out.
Thank you!
